Demographic and ethnicity effects on neuropsychological test performance : implications for dementia assessment in Caribbean populations

Prevalence rates of dementia are increasing worldwide and more so in developing countries. Early and accurate diagnosis of dementia then assumes critical importance. Cross-cultural neuropsychological assessment of dementia depends on the use of instruments that have been appropriately normed and validated for target populations. While culture and ethnicity have been acknowledged as variables which significantly impact cognitive performance, they are not usually included in normative and validation studies. The main aim of this dissertation was to standardise and identify the role played by ethnicity in performance on a number of instruments used in the assessment of dementia and identify the role and interaction of ethnicity with other common demographic variables on performance for Caribbean populations. Performance on the Mini Mental State Exam (MMSE) was influenced by age, education and ethnicity and a validation of corrected scores yielded a cut-off that resulted in a 35% reduction in false positive rates among non-AD persons. The Alzheimer’s Disease Assessment Scale-cognitive section (ADAS-cog) was influenced by education and was resistant to effects of ethnicity. Cut-off scores were lower than traditionally suggested, perhaps due to higher educational levels, but resulted in very high sensitivity (89%) and specificity (89%) rates. Education influenced scores on most measures: digit span, digit cancellation, logical memory, semantic and phonemic fluency and Raven’s Coloured Progressive Matrices. Ethnicity also influenced scores on digit span backwards, digit cancellation, semantic fluency and Raven’ Matrices. Ethnic differences in performance may be attributed to differences in attention, working memory and also to differences in cognitive styles. Differences in educational attainment across cultures and generations renders earlier norms invalid and highlight the needs for norms to be periodically revised in order to be considered representative of current populations. The provision of culturally relevant and contemporary norms yielded in this study can be regarded as invaluable tools in the assessment and diagnosis of dementia in diverse populations

KONCESIJE U ZRAČNIM LUKAMA

In recent years airports have become more commercially oriented and have endeavoured to result in an increasing share of their revenues from non-aeronautical or commercial activities. This paper examines the airport concession sector and the important factors influencing concession revenues. Furthermore, the paper seeks to focus attention on various contract strategies of airport concessions, analyzing the example of Dubrovnik Airport. Contract terms between lessee (concessionaire) and lessor (airport authority) are found to be a significant element for better performance of airport concessions.Posljednjih godina zračne se luke komercijalno orijentiraju i nastoje povećati udio prihoda iz sporednih djelatnosti. U radu se istražuje sektor koncesija u zračnim lukama te važni činitelji koji utječu na prihode od koncesija. Analizirajući primjer Zračne luke Dubrovnik, pozornost se usmjerava na različite modele zaključivanja ugovora za dodjelu koncesijama u zračnim lukama. Uočava se da su uvjeti ugovora između zakupnika (koncesionara) i zakupodavca (operatora zračne luke) značajan element za uspješniju realizaciju koncesija u zračnim lukama

A Wake-Based Correlate of Swimming Performance and Foraging Behavior in Seven Co-Occurring Jellyfish Species

It is generally accepted that animal–fluid interactions have shaped the evolution of animals that swim and fly. However, the functional ecological advantages associated with those adaptations are currently difficult to predict on the basis of measurements of the animal–fluid interactions. We report the identification of a robust, fluid dynamic correlate of distinct ecological functions in seven jellyfish species that represent a broad range of morphologies and foraging modes. Since the comparative study is based on properties of the vortex wake – specifically, a fluid dynamical concept called optimal vortex formation – and not on details of animal morphology or phylogeny, we propose that higher organisms can also be understood in terms of these fluid dynamic organizing principles. This enables a quantitative, physically based understanding of how alterations in the fluid dynamics of aquatic and aerial animals throughout their evolution can result in distinct ecological functions

African American Males\u27 Perception of the Prince Georges\u27 County (MD) Police and Improving the Relationship

The shootings and killings across the country of unarmed African American males by police officers, has become a topic of discussion. Previous research indicates that African American males, in comparison to other groups, are more likely to have adverse encounters with law enforcement officials. The purpose of this phenomenological study was to explore the experiences and perceptions of African American males in Prince Georges\u27 County regarding encounters with the Prince Georges\u27 County Police Department and how the relationship can improve. Max Weber\u27s social action theory was used to examine perception and purposive sampling aided in gathering this information from a group of 10 African American male participants. Interviews were transcribed and then coded and analyzed using a modified Van Kaam procedure. Findings suggest most participants believe Prince Georges County police are doing a good job. The participants also noted specific strategies, including better utilization of seminars, meetings, and other collaborative efforts may improve police-community interactions and relations. The implications for positive social change include recommendations to law enforcement executives in the Prince Georges\u27 County Police Department to utilize the insight gained through this study to better understand how they are perceived by the African American males in the county and strengthen outreach and collaboration efforts. Following these recommendations may improve the nature of police-community relations thereby advancing public safety within the county and with the African American community in particular

Transport and stirring induced by vortex formation

The purpose of this study is to analyse the transport and stirring of fluid that occurs owing to the formation and growth of a laminar vortex ring. Experimental data was collected upstream and downstream of the exit plane of a piston-cylinder apparatus by particle-image velocimetry. This data was used to compute Lagrangian coherent structures to demonstrate how fluid is advected during the transient process of vortex ring formation. Similar computations were performed from computational fluid dynamics (CFD) data, which showed qualitative agreement with the experimental results, although the CFD data provides better resolution in the boundary layer of the cylinder. A parametric study is performed to demonstrate how varying the piston-stroke length-to-diameter ratio affects fluid entrainment during formation. Additionally, we study how regions of fluid are stirred together during vortex formation to help establish a quantitative understanding of the role of vortical flows in mixing. We show that identification of the flow geometry during vortex formation can aid in the determination of efficient stirring. We compare this framework with a traditional stirring metric and show that the framework presented in this paper is better suited for understanding stirring/mixing in transient flow problems. A movie is available with the online version of the paper

A viscosity-enhanced mechanism for biogenic ocean mixing

Recent observations of biologically generated turbulence in the ocean have led to conflicting conclusions regarding the significance of the contribution of animal swimming to ocean mixing. Measurements indicate elevated turbulent dissipation—comparable with levels caused by winds and tides—in the vicinity of large populations of planktonic animals swimming together1. However, it has also been noted that elevated turbulent dissipation is by itself insufficient proof of substantial biogenic mixing, because much of the turbulent kinetic energy of small animals is injected below the Ozmidov buoyancy length scale, where it is primarily dissipated as heat by the fluid viscosity before it can affect ocean mixing. Ongoing debate regarding biogenic mixing has focused on comparisons between animal wake turbulence and ocean turbulence. Here, we show that a second, previously neglected mechanism of fluid mixing—first described over 50 years ago by Charles Darwin — is the dominant mechanism of mixing by swimming animals. The efficiency of mixing by Darwin's mechanism is dependent on animal shape rather than fluid length scale and, unlike turbulent wake mixing, is enhanced by fluid viscosity. Therefore, it provides a means of biogenic mixing that can be equally effective in small zooplankton and large mammals. A theoretical model for the relative contributions of Darwinian mixing and turbulent wake mixing is created and validated by in situ field measurements of swimming jellyfish using a newly developed scuba-based laser velocimetry device. Extrapolation of these results to other animals is straightforward given knowledge of the animal shape and orientation during vertical migration. On the basis of calculations of a broad range of aquatic animal species, we conclude that biogenic mixing via Darwin's mechanism can be a significant contributor to ocean mixing and nutrient transport

Risk factors of child physical abuse by parents with mixed anxiety-depressive disorder or posttraumatic stress disorder

Aim To determine the risk that parents with mixed anxiety and depressive disorder (MADD) or posttraumatic stress disorder (PTSD) will physically abuse their child and evaluate the specific contribution of mental health, perceived social support, experience of childhood abuse, and attributes of family relations to the risk of child physical abuse. Method The study conducted in 2007 included men (n = 25) and women (n = 25) with a diagnosis of MADD, men with a diagnosis of PTSD (n = 30), and a control sample of parents from the general population (n = 100, 45 men and 55 women) with children of elementary school age. General Information Questionnaire, Child Abuse Experience Inventory, Perceived Social Support Scale, and the Child Abuse Potential Inventory (CAPI) Clinical Abuse Scale were used. Results Total results on the Clinical Abuse Scale of the CAPI indicated higher risk of child physical abuse in parents with MADD (273.3 ± 13.6) and in fathers with PTSD (333.21 ± 17.98) than in parents from the general population (79.6 ± 9.9) (F = 110.40, P < 0.001; tPTSD,MADD = 13.73, P < 0.001). A hierarchical regression analysis showed that the greatest predictors in the multivariate model were mental health difficulties, poorer economic status, poor social support, and physical and verbal aggression in partner conflicts. Conclusion Parents with MADD and PTSD exhibit high risk of child abuse. Since parents with PTSD have significantly higher risk of child abuse than parents with MADD, further large-sample research is needed to clarify the relationship between PTSD intensity and the risk of child abus

THE INFLUENCE OF PURCHASE ATTITUDES AND REVIEWS ON USERS’ PURCHASE INTENTIONS IN SOCIAL MEDIA SETTINGS

The rapid growth of social media provides businesses with a new venue for users to make a purchase, as well as the opportunity to post their reviews and comments on products, which can greatly influence the purchase decision process of potential users. The social media platform generates both positive and negative reviews and comments that can influence users\u27 purchase behaviour. In order to gain a deeper understanding of consumer purchase behaviour on social media, the study examines how positive and negative reviews and comments can affect purchase attitudes and pre-purchase behaviour. It also examines how social media users\u27 purchase attitudes contribute to their specific purchase behaviours such as pre-purchase and post-purchase behaviours. The research instrument was a questionnaire, and data were collected through social media platforms using Google forms. Descriptive statistics and Spearman correlation coefficients were used to achieve the objective of this study. The research sample consisted of 162 social media users. The results suggest that there is a positive relationship between purchase attitude and pre-purchase and post-purchase behaviour. The results also suggest that there is a positive relationship between positive and negative reviews and comments, purchase attitude, and pre-purchase behaviour

The flora and vegetation of the NE Mediterranean islet with centuries-long human influences

This paper is based on the main results of an analysis of spontaneous flora and vegetation on the small islet of Vrnik (0.281 km2), on which there are some abandoned limestone quarries, on the eastern Adriatic coast. The investigations were carried out from 2014 to 2016. Altogether, 251 vascular plant taxa (species and infraspecific units) were recorded on the islet. A total of 11 plant associations, one subassocation and two stands within 10 vegetation classes were identified. Due to high anthropogenic influences during the last centuries, quarrying in particular, the islet investigated showed a relatively low variety of vascular plant taxa. In addition, clear signs of fragmentation of the forest vegetation were observed

From the surface to the seafloor: How giant larvaceans transport microplastics into the deep sea.

Plastic waste is a pervasive feature of marine environments, yet little is empirically known about the biological and physical processes that transport plastics through marine ecosystems. To address this need, we conducted in situ feeding studies of microplastic particles (10 to 600 μm in diameter) with the giant larvacean Bathochordaeus stygius. Larvaceans are abundant components of global zooplankton assemblages, regularly build mucus "houses" to filter particulate matter from the surrounding water, and later abandon these structures when clogged. By conducting in situ feeding experiments with remotely operated vehicles, we show that giant larvaceans are able to filter a range of microplastic particles from the water column, ingest, and then package microplastics into their fecal pellets. Microplastics also readily affix to their houses, which have been shown to sink quickly to the seafloor and deliver pulses of carbon to benthic ecosystems. Thus, giant larvaceans can contribute to the vertical flux of microplastics through the rapid sinking of fecal pellets and discarded houses. Larvaceans, and potentially other abundant pelagic filter feeders, may thus comprise a novel biological transport mechanism delivering microplastics from surface waters, through the water column, and to the seafloor. Our findings necessitate the development of tools and sampling methodologies to quantify concentrations and identify environmental microplastics throughout the water column